Cumulative upkeep

Cumulative upkeep is a keyword ability that first appeared in the Ice Age block and then in the Mirage block.

Cumulative upkeep is a triggered ability that increases the cost of a permanent each turn. "Cumulative upkeep cost" means "At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay cost for each age counter on it." If cost has more than one choice, the player chooses separately for each age counter, then pays all the cost or nothing. Partial payments isn't allowed.

If there is more than one instance of cumulative upkeep, each triggers separately, but they both will count the total number of age counters on the permanent.

Mirage was the first set to have benefitial effects that grew as the permanent had more counters, a mechanic used also in Coldsnap.